The reason for trying to list the polar bear as endangered was to force the US government to take action on what threatens it: climate change and the warming of the Arctic. Climate change brought about by unprecedented levels of carbon dioxide in the atmostphere.

What level does atmostpheric carbon need to be at to protect our environment and species like the polar bear? 350 parts per million. That’s a number that may not mean much to most people, but it’s a number 350.org want to become synonymous with the prevention of catastrophic climate change. No Impact Man writes about 350.org in his blog today:

The United States’ most senior climate scientist James Hansen and eight other senior climate scientists have recently deduced, by studying evidence from previous climate swings in our planet’s history, that we must reduce carbon dioxide to 350 ppm or below to avoid rises in sea level, severe changes in weather, droughts, lost of coastal habitat, plagues of tropical diseases, food shortages and on and on.

From 350.org

Our goal for 350.org is simple. We want to bring together an unstoppable movement to spread the most important number on the planet. Scientists like James Hansen of NASA say that 350 parts per million carbon in our atmosphere is the very upper threshold of a safe human climate to avoid ‘an entirely different planet.’ That’s a number the world needs to know – and we need your help spreading it.